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Solid Example: Prefetching

import { ErrorBoundary, For, Suspense, createSignal } from 'solid-js'
import { A } from '@solidjs/router'
import { noop, useQuery, useQueryClient } from '@tanstack/solid-query'
import type { Character } from '~/services/characters/types'
import { charactersQueries } from '~/services/characters/queries'

function CharacterItem(props: {
  char: Character
  onSelect: (id: number) => void
}) {
  const queryClient = useQueryClient()

  const characterQuery = useQuery(() => ({
    ...charactersQueries.detail(props.char.id),
    enabled: false,
  }))

  return (
    <li
      onClick={() => {
        props.onSelect(props.char.id)
      }}
      onMouseEnter={() => {
        queryClient
          .query({
            ...charactersQueries.detail(props.char.id),
            staleTime: 10 * 1000, // only prefetch if older than 10 seconds
          })
          .catch(noop)
      }}
    >
      <div
        style={
          characterQuery.isSuccess
            ? {
                'font-weight': 'bold',
              }
            : {}
        }
      >
        {props.char.id} - {props.char.name}{' '}
        <A href={`/character/${props.char.id}`}>details</A>
      </div>
    </li>
  )
}

function SelectedCharacter(props: { id: number }) {
  const characterQuery = useQuery(() => ({
    ...charactersQueries.detail(props.id),
    throwOnError: true,
  }))

  return <pre>{JSON.stringify(characterQuery.data, null, 2)}</pre>
}

export default function Example() {
  const [selectedChar, setSelectedChar] = createSignal(1)

  const charactersQuery = useQuery(() => ({
    ...charactersQueries.list(),
    throwOnError: true,
  }))

  return (
    <div class="App">
      <p>
        Hovering over a character will prefetch it, and when it's been
        prefetched it will turn <strong>bold</strong>. Clicking on a prefetched
        character will show their stats below immediately, and opening its
        details page will render it without a loading state.
      </p>
      <h2>Characters</h2>
      <ErrorBoundary fallback={(error) => <span>Error: {error.message}</span>}>
        <Suspense fallback="Loading...">
          <ul>
            <For each={charactersQuery.data?.results}>
              {(char) => (
                <CharacterItem char={char} onSelect={setSelectedChar} />
              )}
            </For>
          </ul>

          <h3>Selected Character</h3>
          <Suspense fallback="Loading...">
            <SelectedCharacter id={selectedChar()} />
          </Suspense>
        </Suspense>
      </ErrorBoundary>
    </div>
  )
}